Michael Healy, 62, was found dead in his bedsit at St Luke’s on Wednesday morning.
He had received a blow to the head.
A 38-year-old man was arrested in Passage West at 7.15pm last evening. He was taken to Mayfield Garda station, where he is being questioned under section 4 of the Criminal Justice Act.
Mr Healy was a separated father-of-two and originally from Grenagh in north Cork. He had been working as a taxi driver in the city for the past 10 years. The house at Rocksprings Terrace, where he had a bedsit, was sealed off yesterday as detectives combed the area for evidence.
Mr Healy’s body was found at his home by his brother on Wednesday morning after he became concerned when Mr Healy had not been seen for a number of days.
Gardaí are anxious to know Mr Healy’s routine over the past week and are appealing for anyone with any information to come forward.
Supt Tom Myers, who is leading the Garda investigation, said it was possible that somebody had robbed the taxi driver.
However, he said gardaí were keeping an “open mind” on the motive for the murder.
Anybody with any information is asked to contact the special incident room at Mayfield Garda station at 021 4558519.